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Dredge

A common piece of mining equipment today, the dredge sucks up dirt and gravel from within the stream bed by the use of water pressure. The dredge is operated by the use of a water pump and a network of hoses. Dredge hose sizes can be anywhere from one inch in diameter to 20 inches or more.

A modern dredge works materials, by means of a suction system, which draws gold-bearing materials up through the suction hose by a vacuum effect, from the use of a power-jet intake, which powers the dredge. This allows gold-bearing materials, to be vacuumed up from underwater and processed through a sluice.

The sluicebox contains horizontal ridges or bars, or a series of horizontal channels that act to catch the heaviest particles (the gold) in the slurry as they are vibrated and washed down through the sluicebox. After the slurry has passed the sluicebox it is discharged over the side of the dredge, and should then be directed to a settling pond sufficiently deep and long enough to allow the suspended sediments to settle out.

After a number of hours of operation the contents of the sluicebox are usually transferred to a gold pan, and any gold that was present in the sluicebox can then be collected.

dredge